This invention relates generally to memory storage apparatus and more particularly to an improved disc drive memory storage apparatus having a voice coil linear actuator for reciprocatably positioning a transducer array relative to discs on which the information is recorded. More particularly, the invention is directed to an improved design for the voice coil carriage and printed circuit cable to provide a lightweight, compact and structurally rigid carriage in a disc drive.
Disc drive machines record and reproduce information stored on concentric circular tracks recorded on magnetic discs or equivalent media. The tracks are written and read by transducers which cooperate with the surface of the disc.
The need for compact, high capacity magnetic disc memory storage apparatus has resulted in considerable research into Winchester type disc drives. Due to the increased track density made possible by this research, there has been an ongoing attempt to provide an actuator capable of extremely rapid access time while maintaining the design as structurally rigid and compact. Voice control linear actuators are themselves well known in disc drive technology. Generally they include a carriage which is reciprocatably guided between a pair of carriage guide rails with the data accessing transducers, which are to cooperate with the discs, being mounted on the inner end of the carriage. The motor which drives the carriage is sometimes split into two symmetrical portions disposed on either side of the center line of the carriage to apply equal forces to the carriage generally along parallel lines to drive the carriage toward and away from the discs.
The actuator is situated adjacent the periphery of a stack of vertically spaced discs and is designed to rapidly position the transducers to access the recorded disc information. The transducers normally comprise floating read/write heads for reading and recording information on the tracks of the disc.
Through the present invention is to be described as used in a Winchester disc drive unit, it will be appreciated that the improved actuator and specifically, the improved carriage described herein may be useful in other types of electromechanical memory storage apparatus. It also has potential application to optical memory storage apparatus wherein an optical transducer or several optical transducers are incorporated in the actuator.
In the design of a high performance disc drive such as a high capacity Winchester type disc drive using a linear voice coil actuator motor, a major effort has been made to keep the carriage/coil/transducer assembly compact and lightweight. This is done to make it responsive to imposed forces from the voice coil actuator motor. However, the assembly must also be rigid, and structurally configured to maximize its dynamic response to the electronics which control the carriage position, without creating mistracking problems.